Sky (Non HD) on Media Center PC

My Satellite Setup

My Location
United Kingdom

I know there have been many posts on this subject, but they all contain a lot of different info, so sorry for the repeat question.

I have been running a Freeview based HTPC for almost a year now and am thinking of getting Sky in January (when my current 20Mb Virgin Media Internet package expires), but would like to keep my PC and not use the Sky box if possible.

What is the best way of doing this? I only want normal Sky at the moment as not enough content on HD for me yet, but would like to get something that can work with HD if and when I decide to get it.

My PC spec is:

Core 2 Duo E6320 2x 2MB cache
2GB Crucial Ballistix RAM (2x 1G:cool:
320GB Seagate Hard Disk
MSI 256MB HDMI Graphics card (but am planning to get an 8 series GeForce anyway)
Zalman HD135 HTPC Case
Windows Vista Ultimate (I have both 32 and 64 bit *GENUINE* versions to hand)

I've put the case down as it has built-in iR and would want to continue using it instead of and external dongle if possible.

Thanks and sorry again for the repeat question.